The electrophotographic imaging process is well known. In electrophotography, also known as Xerography, electrophotographic imaging members, such as photoreceptors or photoconductors, have photoconductive surface layers formed on an electricaly conductive substrate or formed on layers between the substrate and photoconductive layer. The photoconductive layer is the top outermost exposed layer and functions as an insulator so that during machine imaging processes, electric charges are retained on its surface.
Electrophotographic imaging members are typically in a rigid drum configuration and/or a flexible belt form. For flexible imaging member belts, they may either be seamed or seamless belts; however, for reasons of simplicity, the disclosures hereinafter will focus only on electrophotographic imaging members in flexible belt form.
Furthermore, the photoconductive insulating layer on the conductive layer is first uniformly electrostatically charged. The imaging member is then exposed to a pattern of activating electromagnetic radiation, such as light. The radiation selectively dissipates the charge on the illuminated areas of the photoconductive insulating layer while leaving behind an electrostatic latent image on the non-illuminated areas. This electrostatic latent image may then be developed to form a visible image by depositing finely divided electroscopic marking particles on the surface of the photoconductive insulating layer. The resulting visible image may then be transferred from the imaging member directly or indirectly (such as by a transfer or other member) to a print receiving substrate, such as paper or transparency. The imaging process may be repeated many times with reusable imaging members.
Xerographic image forming devices have become necessary productivity tools for producing and reproducing documents. Such image forming devices include, but are not limited to, desktop copiers, stand-alone copiers, scanners, facsimile machines, photographic copiers and developers, and multi-function devices and other like systems capable of producing and reproducing image data from an original document, data file or the like.
In typical negatively-charged electrophotographic imaging members, the top outermost exposed photoconductive layer is a charge transport layer. Under normal machine operating conditions, the surface of the transport layer is repeatedly subjected to physical contact from various mechanical subparts, including the cleaning brush, the cleaning blade, the tap bade and image receiving papers. This contact has been found to causes abrasion, scratching and general wear on the photoconductive layer. In particular, loose filler particles, such as crystalline CaCO3, deposited in the image receiving papers are the main source of the early onset of imaging member surface scratching damage. As a result of surface scratching on the transport layer, defects in copy printouts and shortened imaging member function life present a serious problem.
Moreover, the moisture content in the receiving papers has also been determined to be a major contributing factor to deletion defects in copy printouts. Moisture in the material matrix of the receiving paper degrades and impedes toner-imaging capability by reducing the efficiency of toner transfer from the imaging member surface to the substrate. Within the realm of toner degradation, toner “deletion” refers to imperfect formation of toner images onto a print receiving substrate during the toner transfer process. Notably, it has been found that increasingly humid environmental conditions pronounce the effect of deletion development.
Under normal xerographic imaging conditions, toner image print deletion and imaging member surface degradation are two major factors in limiting, copy image quality and imaging member life in image forming devices. As discussed, the loose filler particles and the moisture content in the receiving papers present serious problems in Xerography. Therefore, it is apparent that substantial advancement by way of extending the imaging member service life and suppressing deletion in the printout copy could be achieved by the conditioning unit described in the embodiments of the present disclosure.